Do not call QOpenGLContext::openGLModuleType() from MainDll

In case of dynamic OpenGL on Windows this ends on
calling QWindowsIntegration::staticOpenGLContext() from MainDll
which in case of angle will end up badly.

Add warning message when webengine is loaded from plugin
and context is not initialized.

Task-number: QTBUG-52201
Task-number: QTBUG-55501
Task-number: QTBUG-56020
Change-Id: I03570cad5f686c4a63910c71136bf3eb9499f223
Reviewed-by: Kai Koehne <kai.koehne@qt.io>

1 files changed, 12 insertions, 7 deletions

diff --git a/src/webenginewidgets/api/qtwebenginewidgetsglobal.cpp b/src/webenginewidgets/api/qtwebenginewidgetsglobal.cpp
index e47f135e8..bf3514f71 100644
--- a/src/webenginewidgets/api/qtwebenginewidgetsglobal.cpp
+++ b/src/webenginewidgets/api/qtwebenginewidgetsglobal.cpp
@@ -48,17 +48,22 @@ namespace QtWebEngineCore
 }
 
 QT_BEGIN_NAMESPACE
+
+Q_GUI_EXPORT QOpenGLContext *qt_gl_global_share_context();
+
 static void initialize()
 {
-    //On window/ANGLE, calling QtWebEngine::initialize from DllMain will result in a crash.
-    //To ensure it doesn't, we check that when loading the library
-    //QCoreApplication is not yet instantiated, ensuring the call will be deferred
-#if defined(Q_OS_WIN)
-    if (QCoreApplication::instance()
-            && QOpenGLContext::openGLModuleType() == QOpenGLContext::LibGLES) {
+    if (QCoreApplication::instance()) {
+        //On window/ANGLE, calling QtWebEngine::initialize from DllMain will result in a crash.
+        if (!qt_gl_global_share_context()) {
+            qWarning("Qt WebEngine seems to be initialized from a plugin. Please "
+                     "set Qt::AA_ShareOpenGLContexts using QCoreApplication::setAttribute "
+                     "before constructing QGuiApplication.");
+        }
         return;
     }
-#endif
+
+    //QCoreApplication is not yet instantiated, ensuring the call will be deferred
     qAddPreRoutine(QtWebEngineCore::initialize);
 }